http://arxiv.org/abs/1805.08351
Over-contact binaries are a subclass of eclipsing binaries whose component stars share a common envelope apart from filling their Roche lobes. We conduct a detailed analysis of the underlying nonlinear dynamics of about 463 over contact binary stars, classified as such in the second revision of the eclipsing binary catalog, in the Kepler Field of view (\cite{prvsa2011kepler}). We use two main techniques, namely the correlation dimension($D_2$), calculated from the reconstructed dynamics and the main peak bicoherence function from Fourier transforms of the light curves of these star systems. Our results indicate that almost all the light curves show signatures of deterministic chaos. This will be a helpful addition in understanding the origin of variable maxima and eclipse time variations in eclipsing binaries. We also check for correlations of the bicoherence of the light curves and the fractal properties of the reconstructed phase space of the stars with the inherent properties of the binary, and find that significant correlations exist between many of these properties, the most significant among which is the correlation between the fill-out factor with correlation dimension, $D_2$ and main peak bicoherence, $b_F(f)$. These results indicate that the nonlinear properties of the stars change as the system evolves. These correlations seem to be the first of its kind made between the nonlinear properties of the underlying dynamics of a class of astrophysical objects, and its inherent physical properties.
S. George, R. Misra and G. Ambika
Thu, 24 May 18
45/58
Comments: 9 pages, 11 figures, submitted to MNRAS